/Engine/Source/Runtime/Core/Public/UObject/NameTypes.h
Create anFName. If FindType is FNAME_Find, and the name doesn't already exist, then the name will be NAME_None. The check for existance or not depends on UE_FNAME_OUTLINE_NUMBER. When UE_FNAME_OUTLINE_NUMBER is 0, we only check for the string part. When UE_FNAME_OUTLINE_NUMBER is 1, we check for whole name including the number.
FName ( const WIDECHAR * Name, EFindName FindType )